Histopathologic features of ovaries at increased risk for carcinoma. A case-control analysis.

In this study, the pathogenesis of ovarian carcinoma was investigated by performing a masked histopathologic comparison of benign ovaries removed from 61 women predicted to be at increased risk for developing carcinoma (cases) with ovaries removed from 121 women without known predisposing conditions (controls). The cases included 26 women who had a unilateral invasive carcinoma and 35 women undergoing prophylactic oophorectomy for a family history of ovarian cancer. As predicted by previously developed models, epithelial inclusion cysts were identified more frequently with advancing age in both cases and controls. However, the mean and maximum number of cysts per slide in a woman were not increased among cases. Surface epithelial "atypia," a designation based on a composite impression of multiple features, was found in 13% of cases compared with 3% of controls (relative risk 7.1; 95% confidence interval, 1.9 to 26.1), but this result was based on small numbers. None of the other histologic features examined was found more often in cases following age-adjustment. Reexamination of sections with well-preserved surface epithelium or inclusion cysts under oil immersion demonstrated several differences in the detection of specific features between cases and controls and increased detection of "atypia" among cases, but none of these findings reached statistical significance. It is concluded that there may be subtle differences in the surface epithelium of ovaries predisposed to developing cancer as compared with controls, but these changes are difficult to identify reliably with light microscopy. Future etiologic studies should attempt to optimize specific handling and include molecular studies and epidemiologic analyses.